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Here's one to puzzle over...

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March 14, 2003 4:40:36 PM

I just got called on a hot cpu this morning... 75c on a brand new machine.

When I lifted up the heat sink there was a perfect circle on the top of an AMD xp1700+ palimino where there was no grease. Checking both CPU and Heatsink revealed the same thing... no grease in this little circle right in the middle of the contact point.

Ok, so someone goofed... right? I cleans everything up, puts on some fresh grease and heads out.

An hour later I gets a call and it's hot again... same darned thing, a near perfect circle right in the middle of the CPU's heat island.

I took a machinists die bar to the heatsink, it's within a fraction of a milimeter of perfectly flat... almost no light comes through between the bar and sink at all.

I did the same to the CPU, flat, far as I can tell on such a small surface...

As a precaution I changed both CPU and cooler... Now, I've seen some strange stuff in my day, but this one takes the cake...

Any ideas???




--->It ain't better if it don't work<---

More about : puzzle

March 14, 2003 4:50:27 PM

Any residue on the the core or heatsink? Any residue anywhere (i.e. mobo)? What kind of heatsink are you using? What kind of grease?

Call me Caine.
March 14, 2003 5:18:54 PM

Looks like the grease evaporated. :eek: 
What kind of grease where you using? And what kind of HSF?

My dual-PSU PC is so powerfull that the neighbourhood dims when I turn it on :eek: 
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March 14, 2003 7:54:52 PM

This was Star-tec grease on a Spire Big Rock... a combination I've used dozens of times without a problem.

Obviously something damned weird happened but I don't think evaporation explains a round area with grease all around it... Maybe an air bubble?



--->It ain't better if it don't work<---
March 14, 2003 7:57:12 PM

As I explained, it all looked completely normal except for this small circular spot in the middle...

I tried a different heat sink on that CPU this afternoon, no problem in 2 hours of full load usage.

I tried that heatsink on a different CPU, it ran a little warmer than usual but when I took it apart, the grease was still nice and even on both heatsink and cpu.

It's just damned weird, I tell you! :smile:


--->It ain't better if it don't work<---
March 15, 2003 12:00:02 AM

Well you've heard of crop circles? Now you have core circles. LOL!!!!

Close encounter of the 2nd kind.

<b>99% is great, unless you are talking about system stability</b>
March 15, 2003 5:39:21 AM

Hehe.. no that's just the core... sometimes the process used to make the cores is inperfect and you get a buildup of currents in the center of the die... weird stuff... I see it all the time with PIC's... blows a perfectly circular hole right in the middle of it. This could be the prob.. you e-mailed AMD yet??... They may be interested in looking at that...

To err is human... to really screw things up you need a computer!
March 15, 2003 2:04:01 PM

This might come closer to an explaination than anything so far. But neither CPU nor heatsink have totally failed... The CPU is still working under a different heatsink on my test machine. The heatsink appears ok, but seems to let things get a little warmer than average compared to the dozen or so like it I've installed...

Another plausable explaination would be an air bubble in the grease... but twice in a row? What are the odds of that?







--->It ain't better if it don't work<---
March 15, 2003 3:17:47 PM

Well you get a ring when a fluid dries on a flat surface but this is between two surfaces we are talking about thermal grease.

Pretty strange to me.

What do you program with PICs? My friend makes robots as a hobby.

<b>99% is great, unless you are talking about system stability</b>
March 16, 2003 2:03:09 AM

i've seen something close to it when I did a rush job at installing a heatsink... didn't clean the bottom too well (wipped it but there was oily residue) and the thermal paste just slides right off - it can't bond to it for sh*t, therefore your temps rise, therefore your paste evaporates... maybe :) 

<b>people are only idiots when they don't realize - when they do it just gets funnier, like a dog chasing its own tail, or like george bush's public address(es)</b>
March 16, 2003 12:49:10 PM

It's a possibility...

A friend of mine suggested it might be the heatsink itself. I've tested it on another cpu and it does run hotter than others of the same make and model I've used in the past... I'm thinking it might be a material defect in the cooler.

I've been doing this kind of work for several years now, seen a lot of truly weird stuff but never one like this... And I really don't like dealing with stuff I can't explain...

The mystery continues :smile:



--->It ain't better if it don't work<---
March 16, 2003 6:49:39 PM

tell me about it... i had a mystery with an MSI KT4VL mobo a little while back, took me a month and 3 RMAs to figure-out that it was an issue with the RAM (they claimed it worked with the exact model # i had - it didn't) ... thats the problem with these manufacturer's ratings and compatability tests... sometimes they're a little more leanient on their tests for marketing purposes than is actually workable.

<b>people are only idiots when they don't realize - when they do it just gets funnier, like a dog chasing its own tail, or like george bush's public address(es)</b>
March 16, 2003 7:20:53 PM

I hate crap like that... it's enough to make you pull your hair out.

It seems likely the MSI people listed the memory on specs and didn't really test them at all... Won't be the first time.

I'm tempted to start a new company: "We have no Quality Control inc." The corporate mission statement will be "To sell untested products with an unsupported warranty to unsuspecting customers."







--->It ain't better if it don't work<---
March 16, 2003 8:25:26 PM

hehehehhee. well with MSI I spent hours on the phone (from Montreal Quebec to California = $$) with tech support who literally told me that they didn't knonw what to do and couldn't help me, for future refference anyone who has to deal with MSI tech-support is more likely to get help from future-shop or some other big electronics chain-store... f*ckin idiots... But check this-out, the third board I had MSI send me directly from California, and I dealt with the head techy (I met him at an intel confference around the same time and got his direct number) who supposedly literally tested the mobo with all the components I had on mine... bullshit if you ask me, b/c it never ended-up working..

Thats why I decided a while ago to start learning as much as I could on the hardware and setups I sell, familiarising myself with everything and ONLY selling quality stuff that I've had the opportunity to test-out at my standards. i find some computer resellers are f*ckin idiots sometimes... i mean, there's really a thin line that sepparates the salesmen and the techies who really know their stuff... There's something I tell all my customers/friends when looking at a new computer that I think everyone should keep in mind - if it has an ECS in the specs list the store is trying to rip you off, and if there's no exhaust case fan the guy's just an idiot.

<b>people are only idiots when they don't realize - when they do it just gets funnier, like a dog chasing its own tail, or like george bush's public address(es)</b>
March 16, 2003 9:35:23 PM

Wow... like minds! Pleased to make your acquaintance :smile:

I have a number of preconfigured systems I sell to my customers. I always test the first one practically to the point of destruction before I will sell a number of them. My customers are paying a decent price (amongst the higest in the city) and they expect a reliable machine that will do what they want. I carry the warranties, and service contracts. I don't want to be fixing them every other day. So the first in line always spends a week or so on my bench being run to death in diagnostic burn in programs.

Everything I sell goes out with a 3 year prepaid service contract. My customers never have to pay for labour when I service their machines. They only pay for any parts that are out of warranty. I also install monitoring software in all my machines and inform my customers why it's there and what it does.

I flatly refuse to sell crap.

The way I do things would kill your average computer store where the only focus is on competative pricing.

It's true that most people in the computer industry right now are just box shufflers... I am constantly meeting up with so-called technicians who can't even figure out how to take voltage readings. I see people selling complex systems without any clue why some hardware is better than others. And then there's the one that really gets my goat... the so called software expert who's only answer to system problems is "Format C:"

I flatly refuse to fall to that level... so I got busy and really put my head into the hardware and software. I spend about 1/4 of my work time learning. I won't say there are no mysteries left... that heatsink thing has me beat... but I've not been stumped on a service call in a very long time... and isn't that the way it's supposed to be?



--->It ain't better if it don't work<---
March 17, 2003 2:34:36 AM

Probably due to the flatness of the core and HSF... allthough they look flat there are minute differences. It could be that as the cpu heated up the gunk moves out the way of the bits which are closest together (due to heat and pressure from the heatsink clip) to areas where the distances are greater.

Thus leaving you with your pretty little circle.


And just becuase it LOOKS as if there is no grease doesnt mean there isnt... its probably just a very very VERY thin layer.

<b>Paying for Sex didn?t mean you couldn?t get it any other way - it meant that you could afford the convenience option, same as any other service.</b>
<P ID="edit"><FONT SIZE=-1><EM>Edited by LHGPooBaa on 03/16/03 11:36 PM.</EM></FONT></P>
March 17, 2003 3:44:06 AM

Yup, that is the way its supposed to be... and nice to make your aquaintance too Teq :)  Well, right now my favorite is the systems selling with 2GHz P4s in 'em and 128mb of SDRAM to tell you the truth - I laugh every time I see it. And I know the troubles with not selling crap, and informing the customer of it; its hard sometimes, because I'll have a custy come to me with a part/price list and basically ask what I can do, and when I tell them that I will build them the system only if they sign a contract holding me to no liability, its kind of hard. Good hardware costs money, and we're all in it to make a profit, but it seems like a lot of the time I cut my profits just because I KNOW the customer will go to the chain-store and purchase junk for less, just because its basically my word over theirs, and trust is a hard thing to gain from scratch (though if you do gain the trust of a customer, they're yours till you breakk it). Now about warrantees, its the same with me - I don't even charge labor for building systems, only mark-up on parts (unless I'm upgrading someone's system or cannibalizing an older one, or modifying some hardware or a case)... I tell all my customers that their warrantee is good as long as the manufacturers give me and that they can always call me, whenever, if there's a problem and I'll usually give them a loaner part if I can't replace the damaged one on the spot. But its hard... I mean, I think to myself sometimes that if I would only stoop so low as to use some lesser hardware I could make a couple of more bucks, or attract a couple of more customers, but it's basically ethics over profits.. A friend of mine came to me a couple of weeks ago asking for a computer and how cheap i could throw one together, I said I could do it for $500 (canadian $) but that I would never sell it to him, much less even touch the hardware or embarass myself ordering it from my supplier, there's just some stuff you don't do. Now people also ask me why my computer buzzes and hums like a vaccume cleaner (b/c of all the fans) and I tell 'em straight up, a new computer is loud, no questions about it, because everything gets so damn hot inside... then I make them touch the heatsink on mine after a lil gaming and prove it... then if they're still not convinced, I show 'em tom's video of him removing the heatsink during some unreal 2003 gaming on the athlon core.. sometimes you just gotta see it to believe it.

<b>people are only idiots when they don't realize - when they do it just gets funnier, like a dog chasing its own tail, or like george bush's public address(es)</b>
March 17, 2003 4:18:45 AM

Thought about that... it might just be a wierd coincedence that both Core and Sink have this one spot that fits perfectly.

But that doesn't explain why it darned near hit 80c... In fact, wouldn't that good a fit tend to make it run a little cooler than I'd expect?

Still, it's one of the better ideas put forth to date... thanks.


--->It ain't better if it don't work<---
March 17, 2003 4:35:03 AM

My approach is simple... When I bill out a system, I price all the parts out separately, with warranty expiration dates showing on the invoice. I also price out the labour and on-site service plan separately. Replacement parts are free within their individual warranties (of course) but with the service plan labour is pre-paid for 3 years. The customer and I agree on a bet... I bet my system is so good it won't soak up the service plan... they bet on getting more than the service plan's value if something goes wrong... So far nobody's declined to pay for the service plan, even though it makes my systems among the most expensive in town.

As long as I can sell a new system for everyone that goes off service, I make a decent living. And as a bonus, I get to play with all this really really neat stuff!






--->It ain't better if it don't work<---
March 17, 2003 9:07:58 AM

yeah. proly an unlikely collection of circumstances.

<b>Paying for Sex didn’t mean you couldn’t get it any other way – it meant that you could afford the convenience option, same as any other service.</b>
March 17, 2003 1:47:26 PM

Talking about bad stores... my uncle bought a PC and it had continuesly problems. Turned out to be running out of power and overheating. He had gone to the store he sold it but they said it was due too software and wouldn't even look at it. It is working fine now... after I repaired the mess.
I'm getting more and more friends/family/neighbours that ask for my help when they got problems. It costs them about 1/5 of what a normal PC shop will ask (if not less) and I continue fixing it till I solve the problem(s). Then I run a couple of benchmarks for several hours to test it.
This forum has been a great help to solve problems... there a very few problems I can't solve so far.

My dual-PSU PC is so powerfull that the neighbourhood dims when I turn it on :eek: 
March 17, 2003 3:02:23 PM

Yep, that's how I got started too... A friend of mine noticed that my machine (at the time a p1 200) always seemed at the ready and asked me to look at his. It just kinda spread from there...



--->It ain't better if it don't work<---
March 17, 2003 5:32:57 PM

hmmm, i started out with my P1 133 - before i bought it i did so much research to firgure-out what was what and so i wouldn't get ripped-off, i mean back in the day it costed me $2,400 canadian which equals ~$1,650 US... I mean, I was 13 years old and that was a f*ck load of money to a kid that age, still a nice chunk of cash i would like to have now-a-days ! But yeah, researched everything, and got ripped-off anyways ! Then on I figured I could do the same thing, it was just a puzzle anyways right ? Heh, only thing is I didn't realize how much more there was to it, and as the problems started to arise in my system and others around me (which there weren't even that many of back then... funny to think about it) I started to figure-out what was what. I still remember the first time I figured out how to format my 1.5 Gig HD, hahahahahahah. I needed extra HD space so I deleted my D: partition, which was where I had all my windows OS files to my surprise, I messed myself up pretty well that time - all I was able to save is Doom 1 ! Still have that from my original system, heh, on 5 floppy disks...

<b>people are only idiots when they don't realize - when they do it just gets funnier, like a dog chasing its own tail, or like george bush's public address(es)</b>
March 17, 2003 6:00:40 PM

Heh... sounds like we have a lot in common...

I've also kept everything since MS-DOS 2.0 and have the bottom drawer of my dresser stuffed with floppies, cds and zip disks.

Ancient Chinese curse: "May you live in interesting times"

And... back to the original purpose for this thread... I think I may have figured out what was going on with that hot CPU call. I picked up a new tube of heatsink grease today --this one is Starcraft the old one was Archer-- and it's a lot thicker than the last one. The Starcraft is more like toothpaste and the Archer was like Noxzema. So I did a little test, I did my usual spit an polish on both CPU and Heatsink and put in some of the new stuff... Temperatures back to normal. Ok, says I... try the old stuff... clean it all up and re-assemble... I actually sat and watched it ooze out of the cpu/cooler pressure point as it heated up!

So, I'm thinking it was the thermal compound.

From now on I buy only Starcraft compound, not the Archer stuff... oddly, I got both at radio shack.



--->It ain't better if it don't work<---
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